line = 2;
banner = new Array(
'<a href="http://jp.vctp.com/campaign/2012/2way_012712/index.html" target="_blank" rel="nofollow"><img src="http://jp.vctp.com/img72/archive/img/BN/campaign/2012/2way_012712/500x250.jpg" alt="見せ合いチャット" height="170" width="341" /></a>',
'<a href="http://jp.vctp.com/campaign/2012/show_012812/index.html" target="_blank" rel="nofollow"><img src="http://jp.vctp.com/img72/archive/img/BN/campaign/2012/show_012812/500x250.jpg" alt="リモちゃ完全無料" height="170" width="341" /></a>'
);
rnd = Math.floor(Math.random()*line);
document.write(banner[rnd]);